Abstract [unreadable] [unreadable] The ultimate goal of neural science is to understand how interaction between the peripheral and [unreadable] central nervous systems gives rise to human behavior, how sensory information is processed in [unreadable] our brain and memory to stimulate action. But, as human behavior is mediated by a brain with [unreadable] over 100 billion neurons, a comprehensive and integrative approach all the way from sensory [unreadable] input to motor output is currently unimaginable. The fruit fly Drosophila, with sensory [unreadable] modalities, neural circuits, and complex behaviors that are strongly evolutionarily conserved, [unreadable] has emerged as a model system for neural research. Drosophila is simple enough to be tractable, [unreadable] yet complex enough to be scientifically interesting as well as biomedically relevant. This [unreadable] research program will create new paradigms for understanding perception and voluntary [unreadable] action using larval Drosophila, which has unique advantages for this study. In preliminary work, [unreadable] we have used a novel tracking system to quantify the algorithms that underlie larval [unreadable] chemotactic, phototactic, and thermotactic behavior. Using genetic tools provided by our [unreadable] collaborators and new tools that we are developing for optical physiology and behavior [unreadable] quantification in freely moving animals, we will investigate how pathways within the larval [unreadable] brain use information gathered across the larvum?s sensory periphery to make decisions and [unreadable] result in physical behavior. These individual sensory modality studies are the first steps to [unreadable] understanding this model system?s deeper complexities, the behavioral principles and neural [unreadable] encoding behind the brain?s synthesis of the separate environmental representations provided [unreadable] by multiple senses to result in purposeful and coherent behavior.